Trenching machine



Dec. 9, 1941.. R. H. MCBEAN TRENCHING lMACHINE A .I Filed March '27, 1941 2A Sheets-Sheet l muuu A Traa/vsn Dec. 9, v1941.

R. H. MCBEAN TRENCHING MACHINE 2 sheets-sheet 2 Filed March 27, 1941 A TTV/ENE YS' Patented Dec. 9, 1941 12 Claims.

This invention relates to an excavating or trench digging machine, and more particularly to arr improved trenchv digging machinel having a digging unit which is adapted and arranged to befadjustably lowered to determine the depth of the trenchto be dugorwhich may be raised abovethe machine supporting surface to facilitatemovementof the machine from place' to place,and.wherein the positioning ofthe digging unitn-accomplishedbythe operation of a minimum-numberof controls to thereby simplify the operation of the machine. This, therefore, is tlegenei'alf object of the present invention.

A more'specic object of this invention is to provide trench digging or excavating machine with an improved mechanism for positioningV the diggingunit.

A`- further ob'jectfof the present invention is to provide an' improved' arrangement' for supportin g` 'the digging unit' of 'a wheel type trenching machine 'together'with an' improved power operated mechanism for adjustably positioning the digging.' wheel relative to the machine sup-porting surface.

Other' objects" and features of" this invention will become'n'io'r'e apparent from the following description, .reference being had tothe' accompanying" drawings', wherein I have shown a preferred embodiment'ofthe invention. The essential and novel featur'e'sof the invention will bek summarizedA inthe claims.

Ih'thedra'wings, Fig. 1 is aside elevation of a of the section being indicated by the lines 42---4` onliligV 3, and' Fig. 5`is a fragmentary view simillar to' Figi 1'; butV illustrating a modified form of vthe. invention.

Referring to" the' drawings and' particularly F'ig 1; tnetre'nch digging machine with which tli present' invention' is particularly concerned conipris'e's'ingeneral a main frame lil, mounted on' al' pair' of"trac'to'r b'elt supports,` one of which is'slownin Fig. iat l2. The supports' l2 are each provided' with' a wli'eel' lf3' and a sprocket wheel about which an' endless tractor belt chain I6 is' looped' in the usual manner. Suitable rollers owheels I8, mounted. onthe'supports'lZ, coact with' the belt intermediate th'e sprocket- Wheel `by'a plurality of U-shaped digging"buckets` 4+-,

chinefalongthe entire lower stretch offthe tractor belt.

Mounted at theC extreme forwardend of the frame lo, and disposed* forwardly of the tractor belts` is as-mo'tor; such" asa gasoline engine I=1 of theautomotive type. At the rearward=end of the machinefthere is an inclined guideway- 2i);A As shown inthe drawings, the lowerend of thisguideway is mounted-onithe rearward endof the frame l0 and extends-upwardly and forwardlyvv to a point which, as shown, is'above the tractor belts. Suitable bracing strutsZlare 4provided to insure rigidity of the structure.l TheY guideway 2]V supports, as willA hereinafter be more fully describedf. arearwardly. extending supplemental frame or `boom 25 which carries a digging o-r excavatingunit 2`S.-

The digging unit supporting frame or' boom 25 comprises a' pairof longitudinally extending. spaced'lf'rame membersZ'l' which are connected at their" opposite ends by. crossfrarne'members, onelof whichis shown in Fig. 3 at 28. At its forward end,` theboom 25 is pivotally connected, as by pivot pins so; to a carriage al., 'nus carriag'eis slidably mounted for vertical'movement in the' guideway 28,' which as shown'in Fig.' 4, comprises a p'a-ir ofiinwardly faced channel Ymenibers3'2l. Preferably, the carriage comprisestwo pairs of channel members 35, secured together attl'ieir upper' and' lower ends by cross'members 36;l and? provided'with f-'ront andrear' plates 31', thus'- forming anw enclosedv box-like structure.

The'.T digging'- unit: or digging? wheel' comprises af pair of spaced metal rings; one of which` is shown-inFig l at 49; These rings are'spaced The wheel is disposed between the'fr'ame members'an'd" is'suppcrted at rthree points by pairs ofV rollers @i2 which-engage the'respective rings 45.1 T-hese rollersiare mountedonsuitableshafts journalled in bearings carried`4 by frame struts lie,- which form part ofthe supplemental'framel 25:

Thefdigging wheel'Zli-y and tractor belts IiifareV driven-by the engine Il. Achain, indicatedat 23 on-Figs. 1 and 2 couples the engine with lthe sprocket wheels l5 of the tractor belt assembly` A power transmission mechanism generally indicated'at d5. is interconnected between the engine A lever 46 i-s prosp-rock'et fil. A driving chain 48 transmits the powerN frornthe sprocket 41 to a sprocket wheel il, carried' b'y. th'e supplemental frame 25 and arranged'to engageteeth like formations 5U secured to the ring 40, as generally indicated in Fig. 1. A more complete description of the digging wheel, the digging wheel driving mechanism, as well as a conveyor 5| for ejecting the dug material may be had from reference to the copending application of Vincent S. Penote and Albert R. Askue, Serial No. 299,306, led October 13, 1939.

As heretofore mentioned, the inner or forward end of the boom or supplemental frame 25 is pivotally supported by the carriage 3|. The outermost or rearward end of this boom is preferably supported by a pair of cables 60. As indicated in Fig. 1, the end of each of these cables is secured to the outer end of the supplemental frame 25, as at 6| and the other end of each cable is secured, as indicated in Fig. 4, to the respective winding drums 62. These drums are drivingly secured to opposite ends of a cross shaft 63 mounted in bearings 64, carried by a plate 55 which is secured, as by welding, to the front plate 3'| of the carriage 3|.

Rotation of the cable winding drums 62 results from relative movement between the carriage 3| and its guideway 20. Secured to the shaft 63 are a pair of of gears 66. These gears are drivingly connected with the respective winding drums 62, and are arranged to engage the respective toothed racks B1, which are secured to the side walls of the vertical guideway members 32, as is illustrated in Fig. 4.

The raising and lowering of the supplemental frame 25 and the digging wheel 26 carried thereby is accomplished by a single operating means. As shown in Fig. 3, a hydraulic cylinder 'Ill is secured to the frame l0 and extends upward between the guideway channels 32. Suitable conduits, such as. indicated at 1|, extend from the cylinder 'It to a hydraulic pump T2, driven by the motor in any suitable manner. A valve mechanism, not shown but controlled by a lever 13 is interposed in the conduit 1| to enable the control of the ow of fluid to and from the cylinder 10. The'cylinder 1D is provided with a piston (not shown) having a plunger 14 which extends upward through the cylinder and is secured, as indicated at '|5, to the upper end of the carriage 3|.

The operation of the hydraulic piston mechanism thus moves the supplemental frame 25 and digging wheel 26 from the position shown in Fig. 1 to the position shown in Fig. 2, or vice versa. It is to be noted that as the wheel is raised from the position shown in Fig. 2, the movement of the carriage 3| upwardly in the guideway 32 results in the rotation of the shaft 63 due to the engagement of the gear 66 with the rack 61 carried by the guideway. This results in a constant reeling in of the cables 6B, and causes the outermost end of the digging wheel frame 25 to be raised at a higher rate of speed than the inner end, thus automatically rocking the digging wheel about its pivotal connection with the carriage and assisting materially in decreasing the overall length of the machine.

While Ihave described a cable winding mechanism as a preferred form of supporting and raising mechanism for raising and lowering the outer end of the boom 25, I nevertheless consider other forms of mechanism within the spirit of the present invention. In Fig. 5, I have shown a fragmentary view of a modified form of the invention. In this form rigid bars 60a are used to support the outer end of the digging wheel boom 25.

Each bar 66a is pivotally connected at Bla with the outer end of the boom or digging wheel frame 25, and extends inward to the gear and rack mechanism 66-61 carried by the carriage 3| and guideway 20, respectively. In this form of the invention, gears 80 replace the winding drums 62 on the shaft 62. These gears engage rack formations on the respective bars 60a and serve to rock the boom or supplemental frame about its pivots 30 consequent upon relative movement between the carriage and the guideway.

Each bar 65a is maintained in engagement with its respective gears 80 by a pair of rollers 8| which engage the upper surface of the respective bar. The rollers are journalled in a U shaped bracket 82 which embraces the respective bar 68a and gear 80, and has its legs journalled on the gear shaft 63 heretofore described.

I claim:

1. A trenching machine, a frame carried by propelling and supporting members, a motor on said frame, driving connections between said motor and said propelling members, a substantially upright guideway mounted on said frame adjacent one end thereof and extending upwardly and inwardly from said frame, a carriage slidably mounted in said guideway, a digging mechanism, a support for said digging mechanism, one end of said support being pivotally mounted on said carriage, means acting on said Y carriage and operated by said motor to raise and lower said carriage, means interconnecting the carriage and the outer end of said support, and gear means operated by relative movement between the guideway and carriage and coacting with said connecting means to rock the support in response to the movement of the carriage in said guideway.

2. A trenching machine, a frame carried by propelling and supporting members, a motor on said frame, driving connections between said motor and said propelling members, a substantially upright guideway mounted on said frame adjacent one end thereof and extending upwardly and inwardly from said frame, a digging mechanism, a support for said digging mechanism, one end of said support being pivotally and slidably mounted in said guideway for relatively vertical movement therein, means acting on said end of the support and operated by said motor to raise and lower said support, gearing interconnecting the guideway and the said support and operated by relative movement between the guideway and support, and means operated by said gearing to pivot the support in the guideway.

3. In a trenching machine a frame carried by propelling and supporting members, a motor on said frame, driving connections between said motor and said propelling members, said frame including horizontal frame members and an upstanding guideway, a carriage mounted in said guideway, a digging mechanism, a support for said digging mechanism, one end of said support being pivotally mounted on said carriage and extending outwardly therefrom, means acting on the carriage and operated by said motor to raise and lower said carriage, gears operated by the movement of the carriage in the support, and means actuated by said` gearing to raise and lower the cuter end of said support relative to the guideway and in response to the raising and loweringv of the carriage and at agreaterV ratev of speed than the movement ofthe inner endlv of thecarriage.

4; In a trenching machinea frame carri'edbypropelling andl supporting members, a motoren said frame, said frame including-an upstanding g-uideway, a carriage mounted in said guideway; a diggingl mechanism, a support for said digging mechanism, one end of- 'sa-idsupport beingpivot'- ally mounted on said carriage, means acting on the carriage and operatedlby said motor to raise and lower said carriage, a rack mounted on said guideway, a gear carried by said carriage and meshing with said rack whereby the gear is rotated by movement of the carriage in the guideway, and means actuated by the rotation of said gears to rock the support relative to the carriage and in response to the raising and lowering of the carriage in the guideway.

5. A trenching machine, a frame carried by propelling and supporting members, a motor on said frame, a-n upwardly extending guideway mounted adjacent one end of said frame, a carriage slidably mounted for up and down movement in said guideway, a digging mechanism, a support for said digging mechanism, said support having a pivotal connection with said carriage and extending outwardly therefrom, means acting on said carriage and operated b-y said motor to raise and lower said carriage, a cable winding mechanism mounted on said carriage, said winding mechanism being actuated to wind or unwind a cable by movement of the carriage in the guideway, a cable extending from said winding mechanism to the outer end of said support, whereby the support will be rocked about its pivotal connection with the carriage whenever the carriage moves in said guideway.

6. A trenching machine, a frame carried by propelling and supporting members, a motor on said frame, an upwardly extending guideway mounted on said frame, a carriage slidably mounted in said guideway, a digging mechanism, a support for said digging mechanism extending outward from said carriage, a pivotal connection between one end of said support and said carriage, means acting on said carriage and operated by said motor to raise and lower said carriage, a rack on said guideway, a gear on said carriage and in engagement with said rack whereby relative movement between the carriage and guideway rotates said gear, a cable winding drum mounted on said carriage and driven by said gear, and a cable extending from said drum to the outer end of said support.

'7. A trenching machine, a frame carried by propelling and supporting membersy a motor on said frame, an upwardly extending guideway mounted on said frame adjacent one end thereof, a carriage slidably mounted in said guideway, a digging mechanism, a support for said digging mechanism, one end of said support being pivotally connected to said carriage, means acting on said carriage and operated by said motor to raise and lower said carriage, rigid means interconnecting the carriage and the outer end of said support and operated by relative movement between the guideway and support to raise and lower the outer end of the support in response to the movement of the frame in said support and at a greater rate of speed than the movement of the inner end of said support.

8. In a trenching machine, a frame carried by propelling and supporting members, a motor on said frame, said frame including horizontal framememberswandanupstanding guideway,` a.

carriage mounted said guideway, a-d-i'gging mechanism, asupportlforfsaid'digging mechanism extending outward from said carriage,r one enelV off saidy support beingA pivotallyv mounted on saidv tliecarriage intheV support, and`v rigid means actuated bysai-d:A gearing to rock ysaid supportY relative to saldi carriagei andin. response? tothe raising or lowering of the carriage in the guide- Way.

9. A trenching machine, a frame carried by propelling and supporting members, a motor on said frame, a guideway mounted adjacent one end of said frame andextending upwardly and inwardly therefrom, a carriage slidab-ly mounted in said guideway, a digging mechanism, a support for said digging mechanism, one end of said support having a pivotal connection with said carriage, means operated by said motor to raise and lower said carriage, a rack secured to said guideway, gearing carried by said carriage and engaging said rack whereby relative movement between the carriage and guideway will rotate said gearing, a bar having one end pivotally connected to the outer end of said support and having a rack formation on its inner end to engage said gearing, whereby said support will be rocked about its pivotal connection consequent upon movement of the carriage in the guideway.

l0. In a trenching machine, a main frame, a guideway mounted thereon adjacent one end thereof and extending upwardly therefrom, a digging mechanism, a support for said digging mechanism, a carriage 'slidably mounted in said guideway for relatively vertical movement therein, the inner end of said support being pivotally secured'to said carriage, means acting on said carriage to raise and lower the same in the guideway, a shaft mounted in said carriage, gearing interconnecting said shaft with the guideway, and operative to rotate the shaft consequent with movement of the carriage in the guideway, a winding drum carried by said shaft, and a exible member having one end thereof secured to said winding 4drum and the other end to a point adjacent the outer end of said ysupport, whereby the support will be rocked about its pivotal connection with the carriage in response to the movement of the carriage in the guideway.

1'1. In a trenching machine, a main frame, a guideway mounted thereon adja-cent one end thereof and extending upwardly therefrom, a digging mechanism, a support for said digging mechanism, a carriage slidably mounted in said guideway for relatively vertical movement therein, the inner end of said support being pivotally secured to said carriage, means acting on said carriage to raise and lower the same in the guideway, a shaft mounted in said carriage, gearing interconnecting said shaft with the guideway, and operative to rotate the shaft consequent upon movement of the carriage in the guideway, a gear carried by said shaft, a rack member having one end thereof in engagement with said last-named gear and the other end pivotally connect-ed to the outer end of said support, whereby the support will be rocked about its pivotal connection with the carriage in response to the movement of the carriage in the guideway.

12. In a trenching machine, a main frame, a guideway mounted thereon adjacent one end will rotate whenever the carriage moves in the guideway, a pair of winding drums carried by said shaft, and a pair of ilexible members each having one end thereof secured to a respective winding drum and the other end to a point adjacent the outer end of said support, whereby the support will be rocked about its pivotal connection with the carriage in response to the movement of the carriage in the guideway.

ROBERT H. MCBEAN. 

